Operating characteristic measurement device and methods thereof

ABSTRACT

A device includes an integrated circuit device having a sensor to measure an operating characteristic of the device. The sensor provides information based on the measured operating characteristic to a trigger module. In response to the information indicating the measured operating characteristic meets a threshold associated with a device failure, the trigger module provides an indication to a storage element, which stores information indicating the threshold has been met. In the event of a failure of the integrated circuit device, the storage element can be accessed by a device analyzer to retrieve the stored information to determine the cause of the device failure.

CROSS-REFERENCE TO RELATED APPLICATIONS

The present application is a divisional of U.S. patent application Ser.No. 12/134,748, entitled “Operating Characteristic Measurement Deviceand Methods Thereof” and filed on Jun. 6, 2008, the entirety of which isincorporated by reference herein.

FIELD OF THE DISCLOSURE

The present disclosure relates to devices having an integrated circuitdevice for measuring the operating characteristics of the integratedcircuit device.

BACKGROUND

Failure of an integrated circuit device can result from exposure of thedevice to one of a number of operating characteristics outside aspecified range. Further, combinations of operating circuit conditionscan lead to device failure, even when the operating characteristicsindividually are within specified tolerances. Accordingly, determiningthe cause of integrated circuit device failure can demand a detailedanalysis of the failed device, but such an analysis can be undesirablytime-consuming and expensive. A device and methods for measuring theoperating characteristics of an integrated circuit device wouldtherefore be useful.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a block diagram of an integrated circuit device in accordancewith one embodiment of the present disclosure.

FIG. 2 is a combined block and circuit diagram of a particularembodiment of a trigger module of the integrated circuit device of claim1.

FIG. 3 is a block diagram of an analysis system for an integratedcircuit device.

FIG. 4 is a flow diagram of a method of measuring operatingcharacteristics of an integrated circuit device according to oneembodiment of the present disclosure.

FIG. 5 is a flow diagram of a method of measuring operatingcharacteristics of an integrated circuit device according to anotherembodiment of the present disclosure.

DETAILED DESCRIPTION

A device includes an integrated circuit device having a sensor tomeasure an operating characteristic of the device. The sensor providesinformation based on the measured operating characteristic to a triggermodule. In response to the information indicating the measured operatingcharacteristic meets a threshold associated with a device failure, thetrigger module provides an indication to a storage element, which storesinformation indicating the threshold has been met. In the event of afailure of the integrated circuit device, the storage element can beaccessed by a device analyzer to retrieve the stored information todetermine the cause of the device failure.

Referring to FIG. 1, a block diagram of an integrated circuit device 100is illustrated. The integrated circuit device includes sensors 102 and104, threshold storage modules 110 and 112, trigger modules 120 and 122,a control information module 114, a sensor selection module 118, astorage element controller 140, and a storage element 150. The sensor102 includes an output to provide a signal labeled “S1.” The thresholdstorage module 110 includes an output to provide a signal labeled “TH1”and an input to receive a control signal labeled “C3.” The triggermodule 120 includes an input to receive the signal S1, an input toreceive the signal TH1, an input to receive a signal labeled “C1.”, andan output to provide a signal labeled “T1.” In addition, the triggermodule 120 includes a timer 121.

The sensor 104 includes an output to provide a signal labeled “S2.” Thethreshold storage module 112 includes an output to provide a signallabeled “TH2” and an input to receive a control signal labeled “C4.” Thetrigger module 122 includes an input to receive the signal S2, an inputto receive the signal TH2, an input to receive a signal labeled “C5”,and an output to provide a signal labeled “T2.” In addition, the triggermodule 122 includes a timer 123.

The sensor selection module 118 includes an input to receive the signalT1, an input to receive the signal T2, an input to receive a signallabeled “C2”, and an output. The storage element controller 140 includesan input connected to the output of the sensor selection module 118 andan output. The storage element 150 includes an input connected to theoutput of the sensor selection module 118.

The sensors 102 and 104 are each configured to sense an operatingcharacteristic of the integrated circuit device 100. As used herein, anoperating characteristic refers to a device parameter that affectsoperation of the integrated circuit device 100 and can lead to devicefailure. Examples of types of operating characteristics includeenvironmental characteristics, such as device temperature, pressure,humidity, and the like, electrical characteristics such as voltagelevels, current levels, clock frequency, and the like, and operatingcharacteristics controlled external to the integrated circuit device100, such as a power supply voltage or frequency of an external clocksignal applied to an external pin or other external input of theintegrated circuit device 100. In the illustrated embodiment of FIG. 1,the sensors 102 and 104 are each associated with a different operatingcharacteristic type. For example, the sensor 102 can sense a voltage ofthe integrated circuit device 100, and the sensor 104 can sense atemperature of the device. Each of the sensors 102 and 104 is configuredto provide information indicating the sensed operating characteristicvia an associated output signal. Thus, in the illustrated embodiment,the sensor 102 is configured to indicate the sensed operatingcharacteristic by providing information via the signal S1, and thesensor 104 is configured to indicate the sensed operating characteristicby providing information via the signal S2. In an embodiment, thesignals S1 and S2 are voltage signals, whereby a voltage of each signalis indicative of the sensed operating characteristic. Thus, if thesensor 104 is a temperature sensor, a voltage of the signal S2 can bebased on the sensed temperature. In other embodiments, the signals S1and S2 can be one or more digital signals indicative of the sensedoperating characteristic. In still another embodiment, the signals S1and S2 can be current signals, whereby a current of each signal isindicative of the sensed operating characteristic.

The threshold storage modules 110 and 112 are each configured to storeinformation indicative of an operating characteristic threshold, wherebythe operating characteristic thresholds are based on control informationprovided via the signals C3 and C4, respectively. In the illustratedembodiment, the threshold storage modules 110 and 112 are eachassociated with a different operating characteristic type. Thus, forexample, the threshold information stored at the threshold storagemodule 110 can be indicative of a voltage threshold, while the thresholdstorage information stored at the threshold storage module 112 isindicative of a temperature threshold. In an embodiment, the thresholdinformation stored at the modules 110 and 112 can each be indicative ofa threshold level associated with a failure of the integrated circuitdevice 100. As used herein, failure of an integrated circuit devicerefers to a portion of the device being rendered inoperable due tophysical damage of the device, such that the integrated circuit devicecannot be restored to operability via a device reset or restart. It willbe appreciated that, in the illustrated embodiment of FIG. 1, thethreshold storage modules 110 and 112 are programmable in that theinformation stored at each module can be set based on the associatedcontrol signal. In other embodiments, the information stored at one orboth of the threshold storage modules 110 and 112 can be based on thedesign of the module, such that the information is fixed or hard-wiredin the design.

Failure of the integrated circuit device 100 can result if an operatingcharacteristic meets its associated operating characteristic threshold,either instantaneously or for a particular amount of time. For purposesof discussion, an occurrence of one or more operating characteristicsexceeding a threshold that can lead to failure of the integrated circuitdevice 100 is referred to herein as a failure event. Thus, if theoperating temperature of the integrated circuit device 100 meets atemperature threshold for the device for a designated amount of time,the integrated circuit device is likely to experience a failure eventassociated with temperature.

The trigger module 120 is configured to receive operating characteristicinformation via the signal S1 and operating characteristic thresholdinformation via the signal TH1. The trigger module 120 is configured tocompare the received information and, in response to determining anoperating characteristic of the integrated circuit device 100 has met orexceeded an associated threshold, provide information via the signal T1indicating the threshold has been met. For purposes of discussion, theinformation provided by a trigger in response to an operatingcharacteristic meeting a threshold is referred to herein as triggerinformation. Thus, the provision of trigger information by the triggermodule 120 indicates that the operating characteristic associated withthe signal S1 has met the operating characteristic threshold associatedwith the signal TH1, and therefore indicates that a failure event hasoccurred.

The trigger module 120 can be configured to provide trigger informationin response to an operating characteristic threshold being met for aspecified period of time. In particular, the timer 121 can be configuredto indicate when a designated period of time has elapsed. In response tothe S1 signal indicating the operating characteristic has met thethreshold indicated by the TH1 signal, the trigger module 120 caninitiate the timer 121. In response to determining the operatingcharacteristic meets the operating characteristic threshold for thedesignated period of time, as indicated by the timer 121, the triggermodule 120 can provide the trigger information.

In one embodiment, the trigger module 120 can reset the timer 121 eachtime the operating characteristic does not meet the operatingcharacteristic threshold. Accordingly, in this embodiment triggerinformation will only be provided by the trigger module 120 in responseto the operating characteristic meeting the operating characteristicthreshold continuously for the period of time indicated by the timer121. In another embodiment, the trigger module 120 can suspendadjustment of the value stored at the timer 121, without resetting thestored value, each time the operating characteristic does not meet theoperating characteristic threshold. In this embodiment, triggerinformation is provided by the trigger module 120 in response to theoperating characteristic meeting the operating characteristic thresholdfor the designated period of time in the aggregate. In the illustratedembodiment, the designated period of time indicated by the timer 121 isprogrammable based on control information provided by the signal C1.

The trigger module 122 is configured similarly to the trigger module120, and is configured to provide trigger information via the signal T2based on a comparison of operating characteristic information receivedvia the signal S2 and operating characteristic threshold informationreceived via the signal TH2. In addition, the trigger module 122 can beconfigured to employ timer 123 in order to provide trigger informationbased on the operating characteristic associated with the signal S2meeting the operating characteristic threshold associated with thesignal TH2 for a designated period of time, in similar fashion to thatdescribed above with respect to trigger module 120.

The sensor selection module 118 is configured to receive triggerinformation via the signals T1 and T2. Based on the received triggerinformation, and control information received via the signal C2, thesensor module 118 provides storage information at its output to indicateone or more operating characteristics of the integrated circuit device100 has been met. The storage information can be provided based onindividual operating characteristic thresholds being met, or based on acombination of operating characteristic thresholds being met. Forexample, the sensor selection module 118 can provide the storageinformation in response to a voltage threshold being met, in response toa temperature threshold being met, or in response to a combination ofboth the voltage and temperature thresholds being met at the same time,over the same period of time, or at disparate points in time. The sensorselection module 118 determines which operating characteristics canresult in provision of storage information based on control informationreceived via the signal C2. In addition, the sensor selection module 118can determine other information, such as a date or time that aparticular failure event or combination of failure events occurred.

The storage element controller 140 is configured to receive storageinformation and store it at the storage element 150. In an embodiment,the storage element 150 is configured to maintain stored information inthe absence of power being provided to the integrated circuit device100. Thus, the storage element 150 can be non-volatile memory, such asflash memory or a hard disk, a set of programmable fuses, and the like.The storage element 150 includes a number of storage locations, such asstorage locations 150 and 151, whereby each storage location isassociated with an operating characteristic of the integrated circuitdevice 100. In response to receiving storage information indicating afailure event associated with an operating characteristic has occurred,the storage element controller 140 stores the information at the storagelocation associated with the operating characteristic. For example, inthe illustrated embodiment of FIG. 1, the storage location 151 isassociated with a voltage of the integrated circuit device 100.Accordingly, in response to receiving storage information indicating thevoltage threshold for the integrated circuit device has been met, thestorage element controller 140 stores the information at the storagelocation 151. The storage element controller 140 can also store otherinformation at the storage element 150, such as information indicatingwhen (e.g. a date, time, or combination thereof) that a particularfailure event or combination of failure events occurred.

In an embodiment, each of the storage locations of the storage element150 represents a single bit of information. Accordingly, by setting astorage location to a specified state, the memory controller 140indicates the operating characteristic associated with the storagelocation has resulted in a failure event for the integrated circuitdevice 100.

The control information storage module 114 is configured to storecontrol information for the integrated circuit device 100. In theillustrated embodiment of FIG. 1, the control information storage module114 can store control information designating which operatingcharacteristics of the device are to be measured, the associatedoperating characteristic thresholds, specified timing periods for thetimers 121 and 123, and the like. In an embodiment, the controlinformation is programmable. In another embodiment, the controlinformation is established by the design of the integrated circuitdevice 100. For example, the control information can be fixed orhard-wired by design.

The operation of the integrated circuit device 100 can be betterunderstood with reference to an example. In this example, the sensor 102is configured to sense a temperature of the integrated circuit device100, and the threshold storage module 110 stores information indicativeof a temperature threshold. The trigger module 120 compares the sensedtemperature, as indicated by the signal S1, to the temperaturethreshold, as indicated by the signal TH1. In response to the sensedtemperature meeting the temperature threshold for a designated period oftime (as indicated by the timer 121), the trigger module 120 providestrigger information via the signal T1. In response to the triggerinformation, the sensor selection module 118 determines, based on thecontrol information provided via the signal C2, whether a failure eventassociated with temperature is designated to be recorded at the storageelement 150. If so, the sensor selection module 118 provides storageinformation to the storage element controller 150. In response, thestorage element controller 150 stores an indication of the failure eventat the storage location 152.

Accordingly, in the illustrated embodiment of FIG. 1, the occurrence ofdesignated types of failure events are recorded at the storage element150. In the event of failure of the integrated circuit device 100, thestorage element 150 can be accessed and the recorded failure eventsanalyzed to determine a likely cause of failure of the device. Thus, theneed for expensive and time-consuming analyses to determine a cause offailure for the integrated circuit device 100 is reduced.

Referring to FIG. 2, a combined block and circuit diagram of aparticular embodiment of a trigger module 220, corresponding to thetrigger module 120 of FIG. 1, is illustrated. The trigger module 220includes a timer 221, a comparator 205, and an AND gate 207. The timer221 includes a time threshold module 229, a compare module 225, acounter 218, AND gates 211 and 235, inverter 231, and clock module 215.The comparator 205 includes an input to receive the signal S1, an inputto receive the signal TH1, and an output to provide a signal labeled“T1_RAW.” The clock module 215 includes an output to provide a signallabeled “CLK.” The AND gate 211 includes an input to receive the signalT1_RAW, an input to receive the clock signal CLK, and an output. Theinverter 231 includes an input to receive the signal T1_RAW and anoutput. The AND gate 235 includes an input to receive the signal CLK,and an output.

The counter 218 includes an input labeled “ADJ” connected to the outputof the AND gate 211, an input labeled “RESET” connected to the output ofthe AND gate 235, and an output. The time threshold module 229 includesan input to receive the signal C1 and an output. The compare module 225includes an input connected to the output of the time threshold module229, an input connected to the output of the counter, and an output. TheAND gate 207 includes an input to receive the signal T1_RAW, an inputconnected to the output of the compare module 225, and an output toprovide the signal T1.

The clock module 215 is configured to provide a periodic clock signalvia CLK. It will be appreciated that although for purposes ofillustration the clock module is illustrated as internal to the triggermodule 220, in other embodiments the clock signal CLK can be generatedexternal to the trigger module 220, and can be based on a common systemclock of the integrated circuit device 100.

The time threshold module 229 is configured to indicate a valuerepresentative of a specified amount of time. In one embodiment, thetime threshold module 229 is configured to store the representativevalue in a register or other storage location. In the illustratedembodiment, the specified amount of time can be indicated by controlinformation provided via the control signal C1. The compare module 225is configured to compare time information provided at each of its inputsand provide information at the output indicating whether the specifiedamount of time has been met.

The counter 218 is configured to set a value stored at the counter to aspecified initial value in response to assertion of a signal at theRESET input. The counter 218 is further configured to adjust its storedvalue in response to assertion of a signal at the ADJ input. In oneembodiment, assertion of the signal causes the stored value to beincremented, while in another embodiment assertion of the signal at theADJ input causes a reduction in the stored value. In a particularembodiment, the value stored at the counter 218 is a Gray code value,such that each adjustment of the counter causes a change in a single bitof the stored value.

In operation, the comparator 205 compares the voltage levels of thesignals 51 and TH1, representing a measured operating characteristic andoperating characteristic threshold, respectively. In response todetermining the voltage level of 51 does not meet the voltage level ofTH1 (indicating the measured operating characteristic does not meet theoperating characteristic threshold), the comparator 205 negates thesignal T1_RAW. This causes a reset of the value stored at the counter218 at the next rising edge of the clock signal CLK. In response todetermining the voltage level of S1 does meet the voltage level of TH1(indicating a potential failure event at the integrated circuit device100), the comparator 205 asserts the signal T1_RAW. This causes thevalue stored at counter 218 to be adjusted at each rising edge of theclock signal CLK.

The compare module 225 compares the value stored at the counter 218 toinformation provided by the time threshold module 229. The comparisonindicates whether the measured operating characteristic has met theoperating characteristic threshold for a specified amount of time,thereby indicating whether a failure event has occurred. In response tothe comparison indicating a failure event, the compare module 225asserts a signal at the output. The AND gate 207 performs a logical ANDoperation on the asserted signal and the signal T1_RAW, resulting inassertion of the signal T1. Thus, in response to a failure event, thetrigger module 220 indicates the event by asserting signal T1.

Referring to FIG. 3, a block diagram of a particular embodiment of ananalysis system 301 is illustrated. The system 301 includes anintegrated circuit device 300, corresponding to the integrated circuitdevice 100 of FIG. 1. The system 301 further includes a device analyzer360 and an analyzer interface 365. The integrated circuit device 300includes pins 381, 382, and 383, and storage element 350. The deviceanalyzer includes an output connected to pin 381, an output connected topin 382, and a bi-directional connection to pin 382. The device analyzer360 further includes a bi-directional connection to the analyzerinterface 365.

The storage element 350 is includes storage locations, such as storagelocation 351, that indicate the occurrence of failure events at theintegrated circuit device 300 in similar fashion to that described abovewith respect to FIG. 1. In response to application of supply voltages atthe pins 381 and 383, the storage element 350 is configured to be placedin an accessible state. In an embodiment, the pins 381 and 383 areindependent of other supply voltage pins of the integrated circuitdevice 300, permitting the storage element 350 to be placed in theaccessible state without placing other portions of the integratedcircuit device 300 in an operational mode. This allows the storageelement 350 to be accessible even in the event of a failure of theintegrated circuit device 300.

In the accessible state, the storage element 350 is configured toindicate, in response to requests received via pin 182, the informationstored at one or more storage locations. The stored information isindicated via signals provided to pin 382.

The device analyzer 360 is configured to provide supply voltages to pins381 and 383 of the integrated circuit device 300. Further, in responseto requests from the analyzer interface 365, the device analyzer isconfigured to request the status of storage locations at the storageelement 350 via pin 382, to receive status information in response tothe request, and indicate the status information to the analyzerinterface 365. The analyzer interface 365 is a user interface, such as agraphical user interface (GUI), that is configured to request statusinformation for the integrated circuit device 300 in response to userinteractions with the interface, and to display information indicativeof responses to the request.

The operation of the analysis system 301 can be better understood withreference to an example. In the example, it is assumed that theintegrated circuit device 300 has failed due to a supply voltage meetinga specified level. The failure event causing failure of the integratedcircuit device 300 has been detected and recorded, as described abovewith respect to FIG. 1. In particular, the voltage failure of theintegrated circuit device 300 has been recorded at storage location 351of the storage element 350.

A user has connected the integrated circuit device 300 to the deviceanalyzer 360 for analysis. The device analyzer 360 provides supplyvoltages to the integrated circuit device 300 via pins 381 and 383,thereby placing the storage element 350 in an accessible state. At theanalyzer interface 350, the user requests failure information for theintegrated circuit device 300. In response, the device analyzer 360requests status information for the storage locations of the storageelement 350 via pin 382. The storage element 350 provides the requestedinformation, including the status of storage element 351, via pin 382 inresponse to the request. The device analyzer 360 analyzes the providedstatus information, and determines that the status of storage location351 indicates a supply voltage failure. Accordingly, the device analyzerdisplays information via the analyzer interface 365 indicating theintegrated circuit device 300 failed due to the supply voltage beingmet. Thus, in the illustrated embodiment of FIG. 3, a user can accessfailure information stored at an integrated circuit device, allowing theuser to identify potential causes of device failure without an expensiveand time-consuming analysis of the device.

Referring to FIG. 4, a flow diagram of a particular embodiment of amethod of measuring an operating characteristic of an integrated circuitdevice is illustrated. At block 402, an operating characteristic of theintegrated circuit device is sensed. At block 404, it is determineswhether the sensed operating characteristic meets an associatedoperating characteristic threshold. If not, the method flow moves toblock 406 and a value stored at a timer associated with the sensedoperating characteristic is reset. The method flow returns to block 402to again sense the operating characteristic.

If, at block 404, it is determined that the sensed operatingcharacteristic threshold does meet the operating characteristicthreshold, the method flow proceeds to block 408 and the value stored atthe timer is adjusted. At block 410, it is determined whether the valuestored at the timer indicates that a specified amount of time hasexpired. If not, the method flow returns to block 402. If the specifiedamount of time has expired, the method flow moves to block 412 andinformation is stored indicating that a failure event associated withthe sensed operating characteristic is stored at a storage element ofthe integrated circuit device.

Referring to FIG. 5, a flow diagram of an alternative embodiment of amethod of measuring an operating characteristic of an integrated circuitdevice is illustrated. At block 502, a first operating characteristic ofan integrated circuit device is sensed at the device. At block 504, asecond operating characteristic of the integrated circuit device issensed. In an embodiment, the first and second operating characteristicsare of different operating characteristic types.

At block 506, it is determines whether the sensed first and secondoperating characteristics each meet an operating characteristicthreshold associated with the sensed characteristic. For example, if thefirst operating characteristic is a supply voltage, it is determinedwhether the sensed characteristic meets a specified supply voltagethreshold. If one of the sensed first and second operatingcharacteristics does not meet the associated threshold, the method flowreturns to block 502. If both sensed operating characteristics meettheir associated thresholds, the method flow proceeds to block 508 andinformation is stored indicating a failure event associated with thefirst and second operating characteristics is stored at a storageelement of the integrated circuit device. Accordingly, the methodillustrated at FIG. 5 allows failure events resulting from more than oneoperating characteristic to be stored. For example, the first operatingcharacteristic can be a supply voltage and the second operatingcharacteristic can be a temperature of the integrated circuit device.The illustrated embodiment of FIG. 5 provides for recording of a failureevent resulting from a combination of supply voltage and temperatureconditions.

Other embodiments, uses, and advantages of the disclosure will beapparent to those skilled in the art from consideration of thespecification and practice of the disclosure disclosed herein. It willbe appreciated that, as used herein, an operating characteristicthreshold has been meeted when the operating characteristic fallsoutside of an operating range indicated by the threshold. For example,an operating characteristic threshold associated with a lower boundaryof an operating temperature range will be met if the operatingcharacteristic falls below the threshold. In contrast, an operatingcharacteristic threshold associated with the upper boundary of theoperating temperature range will be met if the operating characteristicfalls above the threshold. It will further be appreciated that, althoughsome circuit elements and modules are depicted and described asconnected to other circuit elements, the illustrated elements may alsobe coupled via additional circuit elements, such as resistors,capacitors, transistors, and the like. The specification and drawingsshould be considered exemplary only, and the scope of the disclosure isaccordingly intended to be limited only by the following claims andequivalents thereof.

What is claimed is:
 1. A method, comprising: sensing a first operatingcharacteristic of an integrated circuit device; in response todetermining the first operating characteristic has met a first operatingcharacteristic threshold, storing at a storage element of the integratedcircuit device first information indicating a failure of the integratedcircuit device; sensing a second operating characteristic of theintegrated circuit device; comparing, at the integrated circuit device,a second operating characteristic threshold to the second operatingcharacteristic; and in response to determining the second operatingcharacteristic has met the second operating characteristic threshold,storing at a storage element of the integrated circuit device secondinformation indicating a failure of the integrated circuit device. 2.The method of claim 1, wherein storing the first information comprisesstoring the first information in response to determining the firstoperating characteristic has met the first operating characteristicthreshold for a specified period of time.
 3. The method of claim 1,wherein the first operating characteristic is of a first operatingcharacteristic type and wherein the second operating characteristic isof a second operating characteristic type.
 4. The method of claim 1,further comprising: sensing a second operating characteristic of theintegrated circuit device; wherein storing the first informationcomprises storing the first information in response to determining thesecond operating characteristic has met a second operatingcharacteristic threshold.
 5. The method of claim 4, wherein the firstoperating characteristic is of a first operating characteristic type andwherein the second operating characteristic is of a second operatingcharacteristic type.
 6. The method of claim 1, wherein the firstoperating characteristic threshold is indicative of a specifiedoperating characteristic associated with a failure of the integratedcircuit device.
 7. The method of claim 1, wherein the first operatingcharacteristic is an environmental operating characteristic.
 8. Themethod of claim 1, wherein the first operating characteristic is atemperature.
 9. The method of claim 1, wherein the first operatingcharacteristic is an electrical characteristic.
 10. The method of claim1, wherein the first operating characteristic is an operatingcharacteristic controlled external to the integrated circuit device. 11.The method of claim 1, wherein determining the first operatingcharacteristic has met a first operating characteristic thresholdcomprises; initiating periodic adjustment of a value stored at a counterin response to the first operating characteristic meeting the firstoperating characteristic threshold at a first time; storing the firstinformation in response to the value stored at the counter meeting atime threshold.
 12. The method of claim 11, further comprisingsuspending periodic adjustment of the value stored at the counter inresponse to the first operating characteristic not meeting the firstoperating characteristic threshold at a second time, the second timeafter the first time.
 13. The method of claim 12, further comprisingresuming periodic adjustment of the value stored at the counter inresponse to the first operating characteristic meeting the firstoperating characteristic threshold at a third time, the third time afterthe second.
 14. The method of claim 11, further comprising resetting thevalue stored at the counter to a specified initial value in response tothe first operating characteristic not meeting the first operatingcharacteristic threshold at a second time, the second time after thefirst time.
 15. A method, comprising: sensing a first operatingcharacteristic of an integrated circuit device; in response todetermining the first operating characteristic has met a first operatingcharacteristic threshold, storing at a storage element of the integratedcircuit device first information indicating a failure of the integratedcircuit device; wherein determining the first operating characteristichas met a first operating characteristic threshold comprises: initiatingperiodic adjustment of a value stored at a counter in response to thefirst operating characteristic meeting the first operatingcharacteristic threshold at a first time; storing the first informationin response to the value stored at the counter meeting a time threshold.16. The method of claim 15, further comprising suspending periodicadjustment of the value stored at the counter in response to the firstoperating characteristic not meeting the first operating characteristicthreshold at a second time, the second time after the first time. 17.The method of claim 16, further comprising resuming periodic adjustmentof the value stored at the counter in response to the first operatingcharacteristic meeting the first operating characteristic threshold at athird time, the third time after the second.
 18. The method of claim 15,further comprising resetting the value stored at the counter to aspecified initial value in response to the first operatingcharacteristic not meeting the first operating characteristic thresholdat a second time, the second time after the first time.